Table 1. Total Gas Production from Different Ratios of SDF Substrates at the Different Time Points of the in Vitro Fermentation (mL/g)^a.

item	SDF 0%	SDF 25%	SDF 50%	SDF 75%	SDF 100%	P value
4 h	5.72 ± 0.09	6.36 ± 0.10	6.30 ± 0.07	6.14 ± 0.07	6.16 ± 0.13	0.2
8 h	5.98 ± 0.12c	7.22 ± 0.04b	7.50 ± 0.06b	7.26 ± 0.09b	7.48 ± 0.16b	<0.01
12 h	5.98 ± 0.12e	6.96 ± 0.10de	7.64 ± 0.13cd	8.04 ± 0.09bc	8.84 ± 0.10b	<0.01
16 h	5.98 ± 0.12e	6.96 ± 0.10de	8.10 ± 0.26cd	8.64 ± 0.12c	11.02 ± 0.16b	<0.01
24 h	6.24 ± 0.09d	12.28 ± 0.10cd	18.02 ± 1.13cd	21.48 ± 1.32c	36.36 ± 2.99b	<0.01
32 h	7.02 ± 0.09f	22.16 ± 0.19e	35.18 ± 1.73d	57.94 ± 1.14c	73.80 ± 1.88b	<0.01
40 h	7.32 ± 0.09f	23.74 ± 0.14e	43.66 ± 1.60d	64.72 ± 0.45c	90.72 ± 1.64b	<0.01
48 h	7.48 ± 0.09f	24.20 ± 0.11e	47.04 ± 1.17d	68.14 ± 0.31c	95.06 ± 0.89b	<0.01

^aData are presented as mean ± SEM (n = 6), and values in the same row with different letter superscripts (b–f) means a significant difference (P < 0.05). SDF 0% means SDF/IDF = 0:1; SDF 25% means SDF/IDF = 1:3; SDF 50% means SDF/IDF = 1:1; SDF 75% means SDF/IDF = 3:1; and SDF 100% means SDF/IDF = 1:0.